emoji

import Foundation


protocol EmojiFetching {
    func fetchEmojiWithSuccesss(_ success: ([String: String]) -> Void, _ failure: (Error) -> Void )
}

class Fack : EmojiFetching{
    func fetchEmojiWithSuccesss(_ success: ([String : String]) -> Void, _ failure: (Error) -> Void) {
        let dic = [
            "fire": "🔥",
            "firetruck": "🚒",
            "heart": "❤️",
            "love": "❤️",
        ]
        success(dic)
    }
}



class EmojiAutoCompletor {
    var dic : [String: String]?
    var fetchor : EmojiFetching
    init(fetchor : EmojiFetching) {
        self.fetchor = fetchor
    }

    func autocompleteWithPrefix(_ prefix : String, _ success: @escaping ([String]) -> Void, _ failure:@escaping (Error?) -> Void){
        if dic == nil {
            //get dic
            fetchor.fetchEmojiWithSuccesss({ (dict) in
                self.dic = dict
                self.findEmojiWithPrefix(prefix, success, failure)
            }) { (error) in
                failure(error)
                return
            }
        }
        findEmojiWithPrefix(prefix, success, failure)
    }
    private func findEmojiWithPrefix(_ prefix : String , _ success: ([String]) -> Void, _ failure: (Error?) -> Void){
        guard let dic = dic else {
            failure(nil)
            return
        }
        //find the prefix in all dictionary
        var res = [String]()
        for (key , emoji) in dic{
            if key.hasPrefix(prefix){
                res.append(emoji)
            }
        }
        success(res)
    }
}






//TEST TEST

let fack = Fack()
let emoji = EmojiAutoCompletor(fetchor: fack)

emoji.autocompleteWithPrefix("firet", { (list) in
    print(list)
}) { (error) in
}